Barn Owl gives an important piece of info - in an emergency, say your climbing a grade where it is almost impossible to turn out and your coolant is about overtemp, engage your heat and it will dump tremendous amounts of heat into the cabin and save your mill, a cold beverage and the knowledge that you saved $$$$$$$$$ not cooking your engine is worth the temporary inconvenience - HTH

So true - and we had done this when going up inclines in very hot weather as a preventative measure previously.

But it's something that needed to be far more instinctual to us when we encountered whatever happened 2 weeks ago. You have only seconds to act - and it's a lot to think about when trying to orchestrate a quick safe stop on the side of the road.

So yes, keep repeating it! This is one thing that might have prevented some damage in our case when Chris started to notice the temp creep up.

I'm fabricating a "dump door" on the bottom of the driver's side heating duct. If needed I can close the interior ducts and open the "dump door", turn the heater on high and effectively add an additional radiator that's almost the size of the engine radiator (not as many rows, but close in sq. in.)

Gordie -

I like this idea! Can you share some pics of the project? How are you planning on controlling this?

I'm fabricating a "dump door" on the bottom of the driver's side heating duct. If needed I can close the interior ducts and open the "dump door", turn the heater on high and effectively add an additional radiator that's almost the size of the engine radiator (not as many rows, but close in sq. in.)

Gordie -

I like this idea! Can you share some pics of the project? How are you planning on controlling this?

Count me in! Great idea.

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L. Christley - W3EYE Amateur ExtraBlue Ridge Mountains, S.W. VirginiaItís the education gained, and the ability to apply, and share, what we learn.Have fun, be great, that way you have Great Fun!

It is hard to guess what the final autopsy will reveal, if anything. A couple of things happened apparently; failure of the air filter and loss of coolant. I don't know if we will ever get to know cause and effect or just coincidence.

At any rate, I think on these older buses which were not originally equipped, a low coolant sensor would be the first thing I would add. That might have saved you.

At any rate, I think on these older buses which were not originally equipped, a low coolant sensor would be the first thing I would add. That might have saved you.

The low coolant sensor alerts based on coolant level in the surge tank reservoir, right?

I think this is probably a good thing to add, but in our case there was still plenty of coolant in the surge tank even after we ended up on the side of the road and we were watching it boil out the overflow and onto the ground.

Is there a way a sensor might have alerted us any sooner than the temperature gauge did?

Is there a way a sensor might have SAVED alerted us any sooner than the temperature gauge did ?

Yup...an automatic over temp shutdown with a pre shutdown warning light....I have piloted Detroits and myriad manifestations of diesel motive haulers...I would not drive MY coach (8v71N) in any part of the LOWER 48 states during daylight without an over temp shut down system.Someone who has done this for the better part of their lives...or repaired the damage caused by neophytes would know that it is impossible to react before implosion in this scenario.

Me I would rather suffer an Emergency over temp shut down on I-45at 4:38 pm....than...well you know...So yes you NEED more sending units and murphy switches or air operated solenoids or something more than whatcha got...as in if I do...you do.PS when I get a pre-over temp light...if I am not already in the right hand lane...it is shut down time here and now and not a muscle twitch later.

Chris, my 79 Prevost, with a 6V92, shuts down right now when the hot indicator comes on, no chance for human reaction time failures, want to be close to,the side ofmthe road when it happens. Oh make sure you take out the cardboard from in front of the radiator:)

Possibly of interest... I've been Googling "digital engine temperature alarms" and have found a couple of good candidates. In the ones I've found, a read-out mounts on the dash and a thermocouple bolts to your choice of spot on the engine. Kinda like a CHT (Cylinder Head Temperature) gauge on an airplane.

The prices I'm finding range from $50 up. A digital gauge provides a more fine level of detail for me, and the set-point of the alarm can be placed to go off a little before things get out-of-hand with shut-offs and such (theoretically). Of course when things happen as quickly as they did with Chris and Cherie all bets might be off, but it's an interesting option.

In your case, it was a catastrophic failure of some kind. Whether it was the air filter or the engine that failed first, we may never know for sure. I'm not sure that any protection system might have "saved" you.Still, I would add a low coolant sensor to my quiver.

I'm not that sure about having an automatic shutdown when you are the exclusive driver of the bus. I think I would prefer a loud, urgent alarm up front and let the driver decide what to do. I can imagine a scenario where I might sacrifice an engine to move a few hundred feet (on a two lane mountain curve for example).

I would agree with this even though we don't know for sure what it was. Probably little could have been done to have salvaged the situation by the time it was realized. Seems like all of the potentially different reaction scenarios would have still given them the same outcome. Play in the sun long enough and eventually you will get rained on, if one doesn't ever want a breakdown, then never go anywhere. Unfortunately, It will be someone Else's turn here all to quickly, I just hope not mine, not yet.

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L. Christley - W3EYE Amateur ExtraBlue Ridge Mountains, S.W. VirginiaItís the education gained, and the ability to apply, and share, what we learn.Have fun, be great, that way you have Great Fun!

One very simple thing I recently did was to move my all-important temperature gauge so it's now front and center, sitting between the speedo and tach. It was previously way off to the left, making it difficult to accurately read exactly what the needle was doing. Now I'll be fixating it on it like I've got some interesting syndrome or something.

And in the space where it used to be I've now got a turbo boost gauge to give me one more thing to worry about!